YSK that if your white dress shirts have brown stains on the collar then take a shower and scrub the dry skin cells around your neck with an exfoliater right before wearing them and you won’t get brown stains.
from /r/YouShouldKnow
YSK说，如果你的白衬衫领口有棕色污渍，那么在穿之前先洗个澡，用去角质剂擦洗脖子周围的干燥皮肤细胞，你就不会有棕色污渍了。